WASHINGTON (NYTIMES) - Mrs Hillary Clinton's campaign is planning its most ambitious push yet into traditionally right-leaning states, a new offensive aimed at extending her growing advantage over Mr Donald Trump, while bolstering down-ballot candidates in what party leaders suggest could be a sweeping victory for Democrats at every level.

Signalling extraordinary confidence in Mrs Clinton's electoral position and a new determination to deliver a punishing message to Mr Trump and Republicans about his racially tinged campaign, her aides said on Monday (Oct 17) that she would aggressively compete in Arizona, a state with a growing Hispanic population that has been ground zero for the country's heated debate over immigration.

Mrs Clinton is "dramatically expanding" her efforts in Arizona, her campaign manager, Mr Robby Mook, told reporters, pouring more than US$2 million (S$2.8 million) into advertising and dispatching perhaps her most potent surrogate Michelle Obama for a rally in Phoenix on Thursday.

In Indiana and Missouri, Mr Mook said, the campaign will spend a total of US$1 million to drive voter turnout, despite what he acknowledged as an "uphill battle" for Mrs Clinton in two states that could determine control of the Senate.

The manoeuvring speaks to the unexpected tension facing Mrs Clinton as she hurtles towards what aides increasingly believe will be a decisive victory - a pleasant problem, for certain, but one that has nonetheless scrambled the campaign's strategy weeks before Election Day: Should Mrs Clinton maximise her own margin, aiming to flip as many red states as possible to run up an electoral landslide, or prioritise the party's congressional fortunes, redirecting funds and energy down the ballot?

Thanks to an infusion of contributions in recent weeks, and what aides describe as a war chest they had maintained in case the opportunity arose, Mrs Clinton is in effect trying to do both.

After nearly eight years in which Democrats on Capitol Hill grumbled about a lack of attention from President Barack Obama, Mrs Clinton has taken care to stay in frequent contact with Senator Chuck Schumer, her former New York colleague, about down-ballot races.

Mr Schumer, poised to be the incoming Senate Democratic leader, and the current leader, Mr Harry Reid of Nevada, met Mrs Clinton's top campaign aides in Washington last month and pressed them to offer financial support for the Senate races, according to a Democratic official briefed on the meeting.

And Mr Schumer has not been shy since about his hope that if Mrs Clinton clearly appeared on her way to winning the race, she would redirect some money to congressional races.

"This is one of many things that the Clinton campaign is doing to help us win a majority in a Senate," Mr Schumer said through a spokesman.

While party strategists are glad to have the money Mrs Clinton is directing from the Democratic National Committee to voter-turnout efforts in Indiana and Missouri, they have little appetite for her to visit those states, where she is likely to lose, because that would make it easier for Republicans to tie Democratic Senate candidates to her.

Democrats are also attempting to unseat Senator John McCain of Arizona from the seat he was first elected to in 1986, but Mrs Clinton's late decision to swoop into that state is not related to his race, which few Democratic leaders believe they can win. Her incursion there is about her own campaign - and the Democrats' desire to focus attention on the damage Trump has done to Republicans with Hispanics.

In particular, Democrats hope to make an example of Sheriff Joe Arpaio, an ardent Trump supporter, by defeating the Phoenix lawman, whose incendiary comments about Hispanics and aggressive tactics with immigrants have garnered attention far beyond his jurisdiction in Maricopa County.

"If Democrats were going to win in Arizona in 2016, you'd need a Republican who turns off Republican women, who really energises Latinos, and you'd need other races on the ground that can really drive engagement - and we have all that," said Mr Andrei Cherny, a former state Democratic chairman.

Ms Alexis Tameron, the state Democratic chairman, said Republican stumbles had allowed local Democrats to "jump our own timeline" for when officials expected to make the state competitive on the presidential level.

"I give credit where credit is due," she said. "And I have been thanking a lot of people, including Donald Trump."

For weeks, Mrs Clinton's team had weighed how seriously to look beyond core battlegrounds like Pennsylvania, Florida and North Carolina, another state that Republicans carried in 2012.

Eager to torment Mr Trump, and the Republicans straining to navigate his erratic bid, her team has also planned at least faint, attention-grabbing plays in other states with little history of Democratic success.

In Texas, the campaign has prepared an ad highlighting Mrs Clinton's endorsement from The Dallas Morning News. And her running mate Tim Kaine has begun sitting for local media interviews in Utah, where Mr Trump has struggled to break away from Mrs Clinton and an independent candidate Evan McMullin in recent polls.

The most brazen push, though, is in Arizona, where the campaign has also scheduled appearances on Mrs Clinton's behalf from her daughter Chelsea and Senator Bernie Sanders of Vermont.

"Donald Trump's hateful rhetoric and deeply disrespectful remarks about Senator John McCain have made Arizona more competitive," Mr Mook said. He added that Mrs Clinton may appear there herself in short order.

"We certainly hope to get her there," he said.

The moves come as Mrs Clinton has more conspicuously emphasised congressional and state races during campaign appearances, taking particular care to mention Senate and even House candidates on the stump and highlighting states that typically receive scant attention from Democrats.

"If you've got friends in Utah or Arizona, make sure they vote, too!" she told voters during a stop in Colorado last week. "We are competing everywhere."

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